<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <link rel="stylesheet" href="./css/高度塌陷.css">
        <title>Document</title>
    </head>
    <body>
        <div id="container">
            <div class="item">111</div>
            <div class="item">222</div>
            <div class="item">333</div>
            <!-- <p style="clear: both"></p> -->
            <!-- 在发生高度塌陷的位置下面添加一个无意义的包含clear属性的元素可以解决高度塌陷 -->
        </div>

        <div id="container2">
            container2的内容
        </div>
    </body>
</html>